Process of making felted, fibrous, waterproof sheets



May 5, 1925.

L. KIRSCHBRAUN PROCESS OF MAKING FELTED, FIBROUS, WATERPROOF SHEETS 3Sheets-Sheet l Filed July 1 1918 HBRAuN May 5, 1925.

L. KIRSC PROCESS OF MAKING FELT-ED, FIBROUS, WATERPROOF SHEETS 3Sheets-Sheet 2 Filed July 1 1918 L KIRSCHBRAUN PROCESS OF MAKING FELTED,F IBROUS,

May 5, 1925.

WATERPROOF SHEETS Filed July 18, 3 Sheets-Sheet 5 Zwfi Patented May 5,1925.

UNIT

LESTER KIRSCHBRAUN, OF EVANSTON, ILLINOIS.

PROCESS OF MAKING .EEIETED, FIBROUS, WATERPROOF SHEETS.

Application filed July 18,

To all who! it may 1'01 :cc/'n.-.'

Be it known that I. TJI'IP IER IImscnnnaurz, a citizen of the UnitedStates, residing in the city of Evanston, county of Cook, and State ofIllinois, have invented certain new and useful Improvements inProcesscs'of Making Felted, Fibrous, ater-proof. Sheets, of which thefollowing is a specification.

This invention relates to improvements in process of making waterprooffelted fibrous sheets, and has among its salient objects to provide aprocess of making felted or sheeted waterproof product used as roofingor covering of various kinds and which consists essentially of a mixtureof fibre, a normally adhesive bituminous binder, and an emulsifyingagent, formed into a tough, solid, dry body; to provide a process whichobviates the necessity of using as a base, prepared felt such as is usedin the manufacture of asphalt shingles and similar elements; to providea process of which the product may have a wide range as to itsflexibility; rigidity, weight and toughness and in-which product asubstantial body portion thereof can be made from relatively chea orwaste material to rovide a rocess of the character referred to in whicha substantial portion of the materials thereof may be such wasteproducts as sawdust, clay,

and the like; to provide a process for forming a product of thecharacter referred to in which the mixture may be fed in an aqueousvehicle or medium continuously to a felting or sheet forming apparatusand there formed into a sheet, and pressed, coated, dried and cut intoany desired shape or size, all as a continuous operation; and in generalto provide certain other improvements in processes of the characterreferred to.

In the drawings- Figs. 1, 1 and 1 taken together indicate more or lessconventionally and diagrammatically,a paper making machine equipped withinstrument alities for practicing the herein described process.

Referring to the drawings,---l designates an emulsifier adapted toreceive asphalt, or

other bituminous binder, liquefied by heat,

an emulsifying agent such as clay, and water, and by proper agitation toemulsify' the asphaltin the water. Theemulsifier comprises a tank of anysuitable construction, which is show; as provided with a rotating shaft2, driven through gears 3 and 4 from any source of power. The shaft- 21918. Serial hTo. 245,470.

carries a series of agitator arms 5 cooperating with, stationary arms 6secured to the side of the tank.

In preparing the emulsion, clay of a colliodal character is put in theemulsifier which has previously been charged with hot water, theproportions being such that a thick paste of doughy or viscousconsistency is produced. Asphalt or other bituminous or pitchy binder,while liquefied by heat, is then slowly stirred into the paste, andwater is gradually added from time to time to maintain the viscousworking consistency. The added water is preferably warm or hot soas tokeep the mass substantially at the approximate melting point of theasphalt. The agitation of these several ingredients disperses theasphalt in a very fine state of division throughout the aqueous mediumcontaining the emulsifying agent. It is to be understood thatemulsifying agents other than clay may be employed, provided an emulsionis produced, which is not of such sticky or adhesive character as tocause it to adhere to the paper making instrumentalities.

This batch contained in the emulsifier can be delivered to a heater 7through pipe 8 controlled by valve 9. The heater 7 is of anyconstruction adapted for converting fibrous stock fibre into pulp and isshown as provided with a-suitable beating roll or rolls 10 and 11. Thepulp which I use may be made from any suitable fibrous material such aspaper waste, tan bark, wood pulp,-

cotton waste, grassy fibres, and hemp. After the fibre is beaten to apulp, the pulp is delivered by means of pipes 12 and 13 and pump 14: toa stufi' chest 15-. This chest 15 is provided with a mechanical agitator16 driven from any suitable source of power. The emulsion instead ofbeing delivered to the beater 7 may be delivered direct to the stuffchest through pipe 17 controlled by valve 18. If the emulsion isdelivered directly to the beater itis closely and thoroughly beaten intothorough admixture with the fibrous stock, and if it isdelivereddirectly to the stock chest it is there mixed with the stock in such away as to thoroughly incorporate it with the latter. It will bedesirable in many cases to add a filler to the mixture which may be ofsuch relatively cheap materials as saw dust, ground cork or any suitablecomminuted material. .It may be desirable to add. more clay to theciently diluted with water to permit the stock to flow freely and thefibers to felt with each other, as is usual in the formation of a papersheet. The various ma terials should be so mixed that the resultingstock shall be free of any tendency 'to be sticky or adhere to themachine It may be here noted that when the emulsified composition isformed,' the particles of the asphaltic or bituminous binder should be 1so thoroughly and finely dispersed through the aqueous paste that theparticles of the binder be efl'ectually separated from each other andsurrounded by the clay and water.

manual manipulation. If properly emulsified it will have a smooth, soapyfeeling andbe free from any tendency to exhibit adhesiveness. By the useof the term emul-' sion of an non-adhesive character I referto acomposition having the character1st1cs herelnbefore referredto. Theexact nature and character of emulsions is not entirely settled andvarious OPlIllOn have been expressed regarding the theory ofemulsification. According to the present invention the asphalt, or analoous pitchy material, while in a melted flui or semi liquid condition, isdispersed in 'very fine particles throughout the aqueous vehicle so thatthe minute particles of asphalt are separated from each other and heldout of contact As the expression has. been used in the arts, the asphaltmay besaid to-lconstitute the internal phase, and

with one another.

the water the external phase. I In any event, thecompositien, ordispersion, as I may termit, is non-adhesive and,

for example, can be readily washed oft-the hands, or off machinery withwater. However, when the water is evaporated or removed, the particlesof asphalt again revert to their adhesive and sticky condition. While itis true that the asphalt may he solid or semi-solid at ordinaryatmospheric.

temperatures, it is in a heated fluid or semiliquid condition whilebeing emulsified and resumes its normal solid or semi-solid con--sistency when the dispersion is cold, without apparently altering thedispersion of, ,the asphalt particles so long as contained in theaqueous vehicle.. It is to be noted that this dispersion is of such acharacter that when it is mixed with the fibrous stock to and formedinto a sheet, the asphalt under: goes no change in character on'constitu-.

tron through the use of chemicals or otherre-agents. 1

After the bituminized stock is thoroughly mixed itis delivered to thesheet forming The operator may ascertain that 20 the emulsification hasbeen sufiicient by roll 58.

mechanism through pipe 20 controlled by valve 21. The delivery end ofthe pipe 20 is provided with outlet 22 which is pref- 'roll 30.

As shown in Fig. 1, the apparatus is broken away to reduce the size ofthe drawings, although the endless screen or wire is .of sufficientlength to allow the desired amounts of water to drain through thescreen. To facilitate the removal of thewater from the sheet, I haveshown; the

usual suction boxes 32 and intermediate pres. sure rolls 33, anadditional suction pipe 34 being rovided to remove water if-desired.

- Inorming, the sheet passes over the foraminated wire or screen on to afabric felt 35, which is trained around a series of rolls 36 and drivenfrom any suitable source of power. Presser rolls 37 may also beprovided. The newly formed sheet a is threaded up over the felt 38 topress rolls 39 and thence up over guide rolls 40 and 4=l.to a series ofdrying rolls 42. The felt38 serves to take up any surplus moisture andreturns over rolls 43.

The felt 35 may be cleaned by-me'ans of rotating brushes 44 and suitableshowers 45. The felt 38 can also be cleaned by brushes 46 and showers47, and the screen by brushes 48 and showers 49. It Will be understoodhow'- ever, that oneof the important features of the present inventionis that the mixture which is to be sheeted is 'of such character that itcan be readily washed oif of the various. felts and will not stickthereto.

After the formed and driedfsheet leaves I provided with delivery pipe 52forthe coating material such as ordinarily employed in the manufactureof prepared roofing, and presser rollers 53 which may be of an suitableconstruction If granular face roofing is being formed, the coated sheetcan be fed beneath hopper 54 containing suitable granular material so asto coyer the face of the roofing. The sheet then coated and covered w1thgranular material is passed between presser rolls 55 and thence overcooling rolls 56 to slitting knives 57 carried by The sheet which is nowsevered longitudinally may be cut transversely to form shingles orshingle strips by passing,

making shingles or shingle strips of prepared roofing such as asphaltshingles and. the like, but it is to he' understood that the sheet afterhaving been formed may be treated in any desired manner, such forexample, as having a design printed thereon,

etc., for use as flooring.

It may be desirable in certain instances to put a granular facing overthe sheet and dispense with the coating. This may be done by impressinggranular material on the sheet through the hopper 61 while the sheet isstill in sufliciently plastic condition to permit the granular orpowdered material to become partially embedded in and adhere to thesheet. In other cases it may be desirable to give a color or luster tothe roofing and this can be accomplished by covering the granular facingof the roofing after. it is applied with a'film of silicate of soda andapigment or dye, the pigment or dye giving the desired color.

In order to more readily practice the invention the followingproportions of ingredients have been found satisfactory in themanufacture of fully saturated roofing felt. To 33 parts dry weight offibrous stock is added an emulsion composed of -parts by weight ofasphalt emulsified with 12 parts by Weight of colloidal clay containedin an aqueous vehicle. It will be understood that these proportions willvary depending upon the nature of the stock and the degree of saturationwith asphalt desired in the finished sheet. Of course, during thesheetforming operation the particles of binder will be distributed amongand. deposited on the fibres in the sheet during the felting of thesame.

By the term bituminous applied to the binder I mean to include thosenatural and artificial asphalts or other residual products of petroleum,coal tar pitch, or other pitches and analogous fusible pitchy orresinous substances, which are normally adhesive or of such an adhesivecharacter that they will not normally in an aqueous medium pass over apaper forming machine Without sticking thereto unless they are convertedto a non-adhesive state. M

I claim as my invention:

1. The process of making afelted water resistant sheet consisting'in sotreating a normally adhesive bituminous water proof binding medium as torender it non-adhesive, mixing it with a fibrous pulp in an aqueousvehicle, passing the mlxture over a paper formmg machlne and'feltmg thefibres, and drying the sheet to cause the binding medium to resume itsadhesive condition.

2. The process of forming a water resist-' ant felted sheet, consistingin treating a normally adhesive bituminous binder toform a non-adhesivedispersion, comprising the binding material suspended in finely dividedparticles in water containing an emulsifying agent, then mixing thedispersion with fibre held in an aqueous vehicle, then felting the stockso formed on a paper forming machine and removing the water to restorethe binder toitsadhesive condition.

3. The process of forming a water resistant felt which consists ofliquifying a bituminous binder with heat, forming an aqueous paste ofwater and colloidal clay, then mixing the liquified binder with saidpaste to produce a non-adhesive dispersion in which the binder is in astate of fine dis persion, mixing said dispersion with fibrous materialin an aqueous vehicle, then felting the stock so formed on a paperforming machine, and finally removing the Water to restore the binder toits adhesive condition.

4. The process of forming a water resistant felted sheet consistinginliquifying a bituminous binder by heat, liquifying colloidal clay withWater to form a paste, mixing said binder and said paste to produce anonadhesive emulsion or dispersion in which the binder is finelydispersed, mixing such dispersion with fibrous material contained in anaqueous vehicle in sufficient proportion finally to produce a Waterresistant sheet, then felting the stock so formed on a paper formingmachine, and finally drying said sheet.

5. The process ofmaking a felted water resistant sheet consisting in sotreating a normally adhesive water proof binding medium to form anemulsion containing the binder, an emulsifying agent and water so as torender the binder non-adhesive, mixing it with a fibrous pulp in anaqueous vehicle and in suflicient proportion finally to produce asubstantial saturation of the'sheet therewith, passing the mixture overa paper forming machine and felting the fibres, and drying the sheet tocause the binding medium to resume its adhesive condition.

6. The process of forming a water resistant felted sheet, consisting inmixing a water proof adhesive bituminous binder, an emulsifying agentand water to produce a non-adhesive composition, mixing fibrousmateri-al in an aqueous vehicle with such proportion ofsaidcompositionfinally to produce a substantial saturation of said sheetwith said binder, then felting the stock so formed on a paper formingmachine, and finally removing the Water to restore the binder toitsadhesive condition.

cles out of contact with one another, then mixing this composition withfibrous material in an aqueous vehicle, then felting the stock so formedon a paper forming machine and removing the water to permit the binderto reassume its adhesive state and unite with the fibres.

8. The process of forming a water resist- 1 ant felted sheet, consistingin treating an adhesive bituminous binder to form a nonadhesivedispersion comprising the binder suspended in finely divided particlesin emulsified form, mixing said dispersion with a sufiicient quantity offibre, to permit of felting, held in an aqueous vehicle, then feltingthe stock so formed on a paper forming machine and removing the waterfor restoring the binder to its adhesive condition.

9. The process of forming a Water resistant felted sheet consisting ofso treating a bituminous binder with water and an agent as to form anon-adhesive composition in which the binder will be held in finelydispersed particles out of contact with one an-.

other, mixing this composition with a fibrous stock. in an aqueousvehicle, feeding said mixture to a paper, or web forming mechanism andforming a felted sheet while the binder is still in 'a non-adhesivecondition and removing the water and causing the binder to reassume itsadhesive state and unite with the fibres.

10. The process of forming a water re- 40 sistant felted sheet,consisting in making a non-adhesive emulsified dispersion fromanadhesive water proof bituminous binder, an emulsifying agent andwater, thoroughly incorporating this dispersion with a fibrous pulp,flowing the stock so formed while the dispersion is still in anon-adhesive condition over mechanism for felting the fibres,

and then removing the water from and drying the sheet so formed wherebysaid binder will reassume its adhesive condition and unite with thefibres.

11. A process of forming a water resistant felted sheet on a paperforming machine,

-consisting in mixing a normally adhesive bituminous binder 'with anemulsifying agent to form an emulsified composition in which the'binderis held in finely divided particles out of contact with one another,then mixing this composition with fibrous 69 stock, then felting thestock-so formed on suitable felting machinery, removing the water, theproportion .of binder being in excess of 10%v by-weight of the finishedproduct. 12. A process of making. a felted waterreliquify the same,

sistant sheet, consisting in so treating a normally adhesive bituminousbinder as to renresistant sheet, consisting in so treating a normallyadhesive bituminous-binder as to render it non-adhesive by causintheparticles to be held apart from each 0t er by the action of asuitable material, mixing such bitumen while non-adhesive with fibrouspulp in an aqueous vehicle, passing such mixture over a paper formingmachine so as to cause the fibres to interlock and interlace, and merelyby removing the water and application of heat to cause the binder totake an adhesive form and unite with the 14. A process of making afelted water resistant sheet consisting in so treatinga waterproofbituminous binder as to render it non-adhesive, mixing the same ,withfibrous pulp in an aqueous vehicle, holding the particles of the binderapart in an aqueous vehicle by the action of a third substance, passingthe mixture over a paper forming machine so as to cause the fibres tointerlock and interlace and then removing the water.

15. The herein described process, which comprises mixing in waterpaper-making stock and an emulsion containing water-- proofing materialand clay,

a paper-making machine a sheet from said mixture.

16. The herein described proces, which comprises mixing in waterpaper-making stock and an emulsion contaim'ngbituminous waterproofingmaterial and clay, and forming on a paper-making machine a sheet fromsaid mixture.

and forming on 17. The herein described process, which comprises mixingin .water paper-making stock an an emulsion containing asphalt and clay,and forming on apaper-makmg v machine a sheet from said'mixture.

18. The herein described process comprising mixing in water,paper-making stock and an emulsioncontaining waterproof ma terial atleast semi-solid at normal atmosheric teniperat'ures and clay, and inform?- mg on a paper-makingmachine a sheet from said mixture.

19. The herein described'process, which;

consists in producing an emulsion by heat-- in a normally adhesivewaterproof binder so idv at atmospheric tem eratures to in ifying saidliqmfied n t an emul iQing-fiagent and water, so that the binderconstitutes 21-. The herein described process, which comprises mixing inWater, paper-making stock and a non-adhesive emulsion containingbituminous waterproofingmaterial emulsified with clay, and forming on apaper-making machine asheet from said mixture.

22. The herein described process, which comprises mixing in water,paper-making stock and a non-adhesive emulsion containing asphalt andclay, and forming on a paper-making machine a sheet from said Hi lxture.

LESTER KIRSOHBRAUN.

